Pivotally mounted capstans



APYiE 1968 R. E. SCHROTER 3,377,438

PI VOTALLY MOUNTED GAPSTANS Filed May 1, 1963 '7 Sheets-Sheet 2 A!)lrifi 1968 R. E. SCHROTER 3,377,438

PIVOTALLY MOUNTED CAPSTANS Filed May 1, 1963 '7 Sheets-Sheet (S IN VEN TOR. M Haw 420155040072? J72 J6! .15 v 7 7 h BY W m April 1968 R. E. SCHROTER 3,377,438

PIVOTALLY MOUNTED CAPSTANS Filed May 1, 1963 7 Sheets-Sheet 4 45 OFF/AM'UIZQWL) 197 220 299 2.21 .495 V '7'06A/EK6' April 1968 R. E. SCHROTER 3,377,43

PIVOTALLY MOUNTED CAPSTANS Filed May 1, 1963 '7 Sheets-Sheet 6 Hm v IN VEN TOR.

p 1968 R. E. SCHROTER 3,377,438

PI VOTALLY MOUNTED CAPSTANS Filed May 1, 1965 '7 Sheets-Sheet 7 INVENTOR fla /4120 5 50/607156 United States Patent ()filice 3,377,438 Patented Apr. 9, 1968 3,377,438 PIVO'IALLY MOUNTED CAPSTANS Richard E. Schroter, Hollywood, Calif., assignor to Ralph J. Samuels, Los Angeles, Calif. Filed May 1, 1963, Ser. No. 277,384 22 Claims. (Cl. 179-4002) This invention relates generally to sound recorders and reproducers, and more particularly to improvements in tape driving and head shifting means for magnetic tape recorders and reproducers of the type which use removable tape cartridges.

More specifically, this invention relates to improvements in miniature tape recorders and reproducers of the type described and claimed in my copending application Ser. No. 261,953, filed Feb. 27, 1963, for Tape Recorder and Reproducer, and assigned to Ralph I. Samuels.

In the aforementioned application Ser. No. 261,953, there are disclosed tape recorders and reproducers that overcome a major stumbling block that had previously existed in connection with miniature tape recorders, namely, that such recorders of the prior art were incapable of both 'high quality reproduction and the long playing times of the suitcase size tape recorders that utilize large reels of tape.

In my co-pending application, a small, removable tape cartridge is disclosed wherein a relatively wide strip of tape adapted for multi-lane recording is wound on a pair of spools, and the tape between the spools is in constant idling contact with a pair of capstans which are continuously rotated in opposite directions. A pair of pressure rollers is also provided to selectively bring about driving engagement between the tape and one or the other of the capstans, and thus control movement of the tape in either of two directions. The present invention is directed primarily to improvements in tape recorders and reproducers using such removable cartridges and continuously rotating, dual capstan drive systems.

Accordingly, a major object of the present invention is the provision of a new and improved tape recorder and reproducer of the type utilizing a wide strip of tape and a multi-position recording and reproducing transducer device.

Another object is to provide a new and improved tape recorder and reproducer which utilizes removable cartridges of magnetic tape, and wherein the tape never has to be handled in any manner.

A further object of the invention is the provision of a new and improved tape driving means for selectively controlling the direction of movement of magnetic tape in a removable cartridge.

Still another object of the present invention is to provide a tape driving means capable of more rapidly reversing the direction of tape movement.

Yet another object of the present invention is the provision of a constantly rotating, dual capstan, tape driving system capable of reversing the direction of tape movement with minimum time lag.

A still further object is to provide a new and improved tape rewind mechanism which is rapid and of simple design.

. Still another object of this invention is to provide new and improved means for incrementally shifting a recording and playback head transversely along a magnetic tape to record and reproduce sounds along multiple lanes of the tape.

Yet another object is to provide, for a magnetic tape recorder and reproducer utilizing a removable cartridge containing a m-ulti-lane tape, new and improved mechanical means for simultaneously controlling the position of a shiftable recording and playback head on the tape and controlling the direction of the movement of the tape.

The above and other objects and advantages of this invention will be better understood by reference to the following detailed description, when considered in connection with the accompanying drawings of an illustrative embodiment thereof, and wherein:

FIGURE 1 is a perspective view of a tape recorder and reproducer, in accordance with the invention, and illustrating the external case and controls;

FIGURE 2 is a top plan view of the recorder of FIG- URE 1, a portion of the top plate being broken away to illustrate internal structure;

FIGURE 3 is a perspective view of a removable tape cartridge for use with the recorder of FIGURES 1 and 2, and shows a pair of guide openings in the cartridge housing for receiving externally operated capstans;

FIGURE 4 is an exploded view of the parts of the tape cartridge of FIGURE 3;

FIGURE 5 is a bottom plan view of the tape cartridge of FIGURE 3, and illustrates the cam surface portions for guiding the oapstans into proper alignment;

FIGURE 6 is a fragmentary sectional view taken along the line 66 of FIGURE 5, and further illustrates the manner in which each capstan is guided by a cam surface into proper alignment for driving the tape within the cartridge;

FIGURE 7 is a bottom plan view of the tape recorder and reproducer of FIGURE 1, a portion of the bottom plate being broken away, and shows the tape driving mechanism in the off position; i

FIGURE 8 is a sectional view, taken along the line 88 of FIGURE 7, and illustrates the means for shifting the flywheels of a pair of capstans into driving engagement with one another;

FIGURE 9 is a fragmentary sectional view, taken along the line 99 in FIGURE 7, and illustrates the detent mechanism for locating the neutral position of the line selector and tape direction control;

FIGURES 10 and 11 are perspective views of the interlock means for preventing the tape recorder and reproducer from being turned off except when the tape driving means is in the neutral state;

FIGURE 12 is a sectional view, taken substantially along the line 12-12 in FIGURE 7, and illustrates the camming means for controlling the line change and tape driving mechanisms of the tape recorder and reproducer;

FIGURE 13 is a fragmentary sectional view, taken along the line 1313 in FIGURE 12, and shows further details of the line change and tape driving mechanisms of the recorder;

FIGURE 14 is a fragmentary sectional view, taken along the line 14-14 in FIGURE 13, and shows the relative positions of the tape spool drive posts and their respective drive rollers when the drive system is in neutral;

FIGURE 15 is a fragmentary sectional view, similar to that of FIGURE 12, but with the camshaft and cam followers in their proper positions for the rewind state of the drive system;

FIGURE 16 is a fragmentary, side elevational view, taken in the direction of the arrow 16 in FIGURE 2, portions being broken away to illustrate the over-all gearing relationship between the manual line change mechanism, the camshaft and the automatic line change mechanism;

FIGURE 17 is a sectional view, similar to that of FIGURE 12 but with the camshaft and earns in their positions for placing the tape driving system in the forward state;

FIGURE 18 is a sectional view, taken along the line 1818 in FIGURE 17, and illustrating the tape spool drive means and the automatic line change triggering mechanism;

FIGURE 19. is a fragmentary sectional view, taken along the line 19-19' in FIGURE 18, and shows the relative positions of the tape and tape spool drive elements immediately after a line change and reversal of the direction. of tape movement;

FIGURE 20 is. a fragmentary sectional view, taken along the line 20-20. in FIGURE 19, and illustrates one: of a pair of spring-loaded plungers adapted for tape cartridge ejection;

FIGURE 21 is a fragmentary, partially schematic view illustrating the cooperation between one of the cam followers and an electrical switch for controlling the erase signal input to a tape head assembly;

FIGURE 22 is a front elevational view of the recorder of FIGURE 1, with the cartridge compartment cover in the open position;

FIGURE 23 is a. fragmentary sectional view, taken along, the line 23-23- in FIGURE 22, illustrating the gear arrangement. for shifting the recording andplayback head,

and the camming. arrangement for controlling the position of the tape pressure pad;

FIGURE 24 is a. sectional view, taken along the line 2*4-24 in FIGURE 23, and illustrating further details of the tape drive and automatic line changing mechanisms;

FIGURE 25 is a fragmentary perspective view, taken in the direction of the arrow 25 in FIGURE 24, and

illustrates the trigger mechanism for the automatic line changer;

FIGURE 26 is a fragmentary perspective view illustrating a hole atone end of a length of tape, such hole being used to trip the trigger mechanism shown in FIG- URE 25;

FIGURE 27 is a fragmentary perspective View, taken in the direction of the arrow 27 in FIGURE 24, illustrating' the automatic line change mechanism at one end of the camshaft;

FIGURE 28 is a fragmentary view, taken in the direction of the arrow 28, in FIGURE 27, and illustrates portions of the trigger mechanism for the automatic line change ratchet;

FIGURE 29 is a fragmentary sectional view, taken along the line 29'29 in FIGURE 27, and illustrating the spring drive for the automatic line change ratchet mechanism, as well: as the controlled slippage system for coupling the camshaft to the line change mechanism;

FIGURE: 30 is a sectional view taken along the line 30'30 in FIGURE 29; and

FIGURES 31 and 32 are sectional views, taken along the line, 31-31 in FIGURE 12, and illustrating the stop mechanism for limiting rotation of the camshaft and transverse shifting of the recording and playback head.

Referring now to the drawings, and particularly to FIGURES 1, 2 and 7 thereof, there is shown a tape recorder and reproducer having an external casing or housing 42. A machine on-oif' control knob 44' and tape direction and line selector control knob 46 project through.- the front fme of the housing 42 at opposite ends thereof. The control knob 46 is afiixed to one end of a pivotal shaft 49, the pivotal position of the shaft determining whether the tape drive system is in the forward, neutral, or rewind state. Rotation of the knob 46 and shaft 49 causes incremental shifting of a head assembly todifferent transverse positions relative to a tape, the position of the head assembly being, indicated upon a numbered disc. 4'7- at one side of the housing 42.

The front. face of the housing 42 is also provided with .a. hinged, cover plate 48 for selectively shielding and exposing, a tape, cartridge compartment within the recorder. The cover. plate; 48 can be locked in the closed position by an appropriate sliding latch 50 controlled by a latch handle 52 extending from the forward face of the cover plate 48.

As shown in FIGURES, 2, 7', 13 and 19, the removable tape cartridge 54, once inserted into the recorder 40,. automatically engages a pair of tape driving capstans 56,

57. The construction of the removable tape cartridge 54, and its cooperation with the driving capstans 56, 57, are best observed in FIGURES 3-6.

The cartridge 54 includes a housing 60 having a thick internal section 61. The inner surface of the section 61 is formed with a pair of curved portions 62, 63, each portion having a radius of curvature to match that of the flanges of a pair of spools 64, 65 by which a length of magnetic. tape 66 is carried.

The section 61 may be a molded insert, e.g., of plastic or the like. The front surface of the section 61 is spaced sufficiently behind the front of the housing 60 to provide a space or channel for the tape 66. When the spools 64, 65 are located within the housing 60, the tape 66 thereon is passed between the spools and a pair of rods 68', 69 which extend through the housing outboard of and parallel to the spools, and the. tape passes through the space between the section 61 and the front of the housing. The rods 68, 69 also aid in locating the spools 64, 65.

The end surfaces. of the section 61 are spaced from the ends of the housing 60, to facilitate looping of the tape 66 over the section 61 during assembly of the cartridge 54. Furthermore, the ends of the section 61 are tapered, so that the section is generally trapezoidal Y in shape. Preferably, these end surfaces of the section .61

are also. concave.

At opposite ends of the housing 60', slotted openings 70, 71 are provided which have, their outermost ends aligned with respective openings 72, 73, and the innermost ends of the slotted openings 70, 71 are aligned with the innermost portions of the tapered end surfaces of the section 61.

Referring to FIGURE 5, it will be observed that, by virtue of the shapes of the section 61 and openings 70-73, when the tape 66 is passed over the front surface of the section 61, there is a substantial clearance between the tape and the ends of the shorter side of the section 61. The significance of this arrangement will be apparent in FIGURE 6, which shows the manner in which the driving capstans 57, 5 9 are automatically pro perly aligned for driving the tape 66 upon insertion of the cartridge 54 into the recorder 40. Although FIGURE 6 illustrates alignment only of the single capstan 57, both of the capstans 56, 57 are identical, and it is to be understood that alignment of the capstan 56 by insertion of the cartridge 54 is accomplished in exactly the same mannet as shown for the capstan 57.

For purposes of discussion, it will be assumed thatv both capstans 56, 57 are pivotally mounted and have their outer ends normally biased towards each other. The specific manner in which the capstans 56, 57 are supported will be subsequently pointed out in connection with the detailed description of the drive system.

'In the innermost positions of the capstans 56, 57, their outer ends are in position to be engaged by the inner portions of the end surfaces of the section 61, when the cartridge 54 is positioned so as to move it into place in the cartridge compartment below the hinged cover plate 48 (see FIGURES 2, 7, 22 and 23). To aid in this regard, the outer ends of the capstans are tapered to insure their entering the space between the. tape 66 and the end surfaces of the section 61.

As indicated by the dotted and phantom positions of the capstan 57 in FIGURE 6, one of the end surfaces, of the section 61 effectively cams the capstan outwardly. While thus being cammed, the capstan 57 inherently moves the tape 66 outwardly with it. When the cartridge 54 is locked in place within the recorder 40, both of the capstans 56, 5-7 have been brought into proper alignment. adjacent the tape 66 (see FIGURE, 19).

The shapes of the section 61 and the openings 70, 71 are chosen to insure that the capstans are properly cammed outwardly to their proper positions adjacent the tape 66. If desired, the section 61 may be rectangular in shape rather than trapezoidal, in which case the openings 70, 71 are appropriately shaped, e.g., pear-shaped, to effect the desired camrning action upon the capstans.

With the cartridge 54 inserted into the recorder 40, the outer end of each of the capstans 56, 57 extends through the openings 72, 73 respectively, and the top face 'of the cariridge 54 (see FIG-URES 6 and 22). The outer ends of the capstans 56, 57 are bearing caps 75, 76, respectively, which are rotatably mounted on the ends of the capstans. These bearings caps 75, 76 are frictionally held in the circular openings 72, 73. Hence, lateral play of the capstans 56, 57 is substantially eliminated, because each capstan rotates within its fixed bearing cap. The bearing caps 75, 76 also prevents rotational contact of the capstans with portions of the cartridge 54 other than the tape 66. Otherwise, portions of the cartridge in contact with the rotating capstans, as well as the capstans themselves, would wear rapidly.

Referring now again to FIGURES 3-5, the section 61 is provided with a central depression or recess 78 in its front surface. This arrangement permits the tape 66 to slide between a magnetic head assembly 80 and a pressure pad 82 when the cartridge 54 is inserted into the recorder 40 (see FIGURES 22 and 23). In this connection, a guide 83 is mounted within the cartridge compartment of the recorder to seat within the recess 78 when the cartridge is inserted.

As will be noted in FIGURE 3, the front of the housing 60 is provided with openings 84, 85, to permit entrance of a pair of line change triggers 87, 88 (see FIG- UR'ES 7, 18, 24 and 25). In this connection, it should also be noted that the section 61 also has spaced shelflike surface portions with recesses 90, 91 aligned with the openings 84, 85, respectively, to provide clearance space into which the line change triggers may move when openings in the tape 66, such as the trigger opening 93 shown in FIGURE 26, pass behind the triggers.

To facilitate assembly of the tape-filled cartridge 54, the housing 60 may be formed in two parts 95, 96. The rods 68, 69 are integral with one part 96, and both parts 95, 96 have slots in their front surfaces so as to form the openings 84, 85 when the two parts are secured together.

The section 61 is positioned in one part 96 of the housing 60. The spools 64, 65 with the tape 66 thereon are positioned to fit in the curved wall portions 62, 63. Then the tape 66 is looped over the section 61. The other part 95 of the housing 60 is then secured in place. In this connection, the two parts 95, 96 of the housing 60 may be secured together by screws 98 for securing the part 95 to the outer ends of the rods 68, 69, and by screws 99 for securing the part 95 to the section 61.

The housing 60 also has a pair of openings 101, 102 in its underside (see FIGURES 4 and 5). When the cartridge 54 is moved into place within the recorder 40, the openings 101, 102 receive suitable support elements in the form of flanges 104, 105, respectively, carried at the lower ends of a pair of spool drive posts 107, 108 (see FIGURES 2, 18, 19, 23 and 24).

As best observed in FIGURES 2, 7, 12, 1 7 and 19, movement of the tape 66 is aided by two banks of pressure rollers 109, 110 which straddle the cartridge 54. In this connection, the corners of the cartridge housing 60 are cut away to provide access openings 112, 113, and thereby permit the rollers 109, 110 to selectively engage the tape 66 and press it against one of the capstans 56, 57, respectively.

As will be apparent in FIGURES 2, 8, l7 and 19, the tape driving capstans 56, 57 are adapted for continuous rotation in opposite directions. Hence, to move the tape from right to left in FIGURE 17, the pressure rollers 109 are moved into engagement wit-h the tape 66, so that the capstan 56 controls the movement of the tape. Similarly, to move the tape 66 from left -to right, the rollers 109 are moved out of engagement with the tape and the rollers 110 are brought into engagement with the tape, so that the capstan 57 controls the movement of the tape (see FIGURE 19). When the tape drive system is in neutral as shown in FIGURE 12, neither of the pressure rollers 109, is in engagement with the tape 66. In this case, neither capstan 56, 57 imparts any movement to the tape 66, and the tape remains stationary. The reason for this is that, although both capstans are at all times in 'contact with the tape 66, until the pressure rollers 109 or 110 are brought into engagement with the tape 66 to press it against one or the other capstans 56, 57, there is insufl'lcient frictional force between either capstan and the tape to drive the tape. Therefore, the capstans merely idle adjacent the tape, with total slippage between the surface of the tape and each capstan surface, until one of the pressure rollers 109, 110 is brought into contact with the tape to press it against one of the capstans.

Referring to FIGURES 2 and 24, it will be observed that a pair of posts 115, 116, "at opposite ends of the cartridge compartment in the recorder aid in guiding the cartridge 54 during its insertion into the recorder. These posts 115, 116 minimize lateral play of the cartridge while it is being inserted. It will also be noted in FIG- URES, 2, 19, 20 and 24, that a pair of spring-biased rods 118, 119 are disposed below the cartridge 54 at opposite ends thereof, and are adapted to bias the cartridge upwardly as seen in FIGURE 2. Hence, when the cover plate 48 is unlatched and opened the cartridge '54 rises for ease of accessibility during removal.

The housing 60 of the cartridge 54 isprovided with recesses 121, 122 at both sides (see FIGURES 35) which are adapted to receive the guideposts 115, 116 in the cartridge compartment of the recorder (see FIGURE 22). When the cartridge 54 has been completely inserted, the cover plate 48 is closed and latched, and the cartridge is held in position by a pair of resilient bumper elements 124, 125 secured to the inside face of the cover plate (see FIGURES 18, 22 and 23).

Referring now to FIGURES 2, 7 and 8, the capstans 56, 57 each pass through slightly oversized openings in a pair of mounting brackets 125, 126, respectively, and have their lower ends secured to a pair of flywheels 128, 129, respectively. An electric motor :131 is mounted within the recorder 40 below the flywheels 128, 129 (see FIG- URES 2, 7, 8 and 13) to present its output shaft 132 in driving engagement with a resilient peripheral rim 134 of the flywheel 129. The output shaft 132 is provided with a portion 136 of enlarged diameter at its upper end, and this enlarged diameter portion is in driving engagement with a resilient roller 138 aflixed to a shaft 140 which supplies motive power to the system for selectively imparting rotary motion to the spool drive posts 107, 108 (see FIGURES 2, 7,8, 13 and 18).

As shown in FIGURES 7 and 8, the flywheels 128, 129 are normally held apart when the control knob 44 is in the ofi? position, and the flywheels are brought into driving engagement with one another when the recorder 40 is turned on as shown in FIGURE 2. This is accomplished by mounting lower flywheel hub projections 142, 143 so that they rest, via reduced diameter portions 145 passing through slightly oversized holes, in a pair of L-shaped support plates 147, 148 (see FIGURES 8 and 18). The reason for the slightly oversized holes is to permit suflicient play so that the capstans 56, 57 can be pivoted towards each other for proper insertion of the cartridge 54 into the recorder. The capstans 56, 57 are normally biased towards one another by the leaf spring elements 150, 151 shown in FIGURES 2 and 24.

Referring now more particularly to FIGURE 8, the L-shaped plates 148, 149 are each pivoted about pins 152, 153, respectively, at the plate. A single in 155 passes through overlapping portions of the shorter legs of both plates 147, 148. The pin 155 also passes through a clearance slot 157 in a horizontal support member 158 and through a cam slot 160 in a slide bar 161 adapted to move along the upper face of the support membe'r l58. The free ends of the longer legs of the L-shaped plates 147,

7 148 are each provided with transverse clearance slots 163, 164 through which pins 166, 167, respectively, pass. The longer legs of the plates 147, 148 are coupled together by means of a coil spring 170, so that the longer legs, and hence the flywheels 128, 129, are biased towards each other.

When the slide bar 161 is in the extreme right position in FIGURE 8, the pin 155 is cammed to a position which causes the plates 147, 148 to overcome the biasing force of the spring 170 and pivot about their pins 152, 153, respectively. This causes the flywheels 128, 129 to move out of engagement and away from each other. However, if the slide bar 161 is moved to the left, the pin 155 is no longer cammed to a position which forces the flywheels to move away from each other, and the spring 170 will cause the plates 147, 148 to pivot so that the flywheels are again brought into engagement.

The position of the slide bar 161 is controlled by a pivotal arm 172 (see FIGURES 7, 8 and 18). The arm 172 extends along one side of the recorder housing and is pivoted at 173. The lower end of the arm 172 is pivotally coupled to one end of the slide bar 161 at 175, whereas the upper end of the arm is pivotally coupled to a rotatable plate 177 (see FIGURES 7 and 18). The plate 177 is, in turn, affixed to the lower end of the shaft 179 upon which the on-off control knob 44 is mounted. Hence, operation of the control knob 44 causes the slide bar 161 to move one way or the other and thus shift the flywheels 128, 129 into or out of driving engagement with each other.

When the control knob 44 is in the off position, the flywheels 128, 129 are out of engagement as shown in FIGURES 7 and 8. When the control knob 44 is in the on position, the flywheel 128 and peripheral rim 134 of the flywheel 129 are brought into driving engagement. Since the rim 134 of flywheel 129 is driven by the output shaft 132 of the motor 131, contact of the flywheel 128 with the rim 134 causes the flywheel 128 to also be driven, but in the opposite direction of rotation than the flywheel 129. Hence, both capstans 56, 57 rotate in opposite directions, as indicated in the previous general discussion, when the control knob 44 is moved to the on position. In this connection, it will be observed in FIGURE 8 that the slide bar 161 also carries a transverse finger 181 adapted to trip a two-position electrical switch 183 through which electrical power is supplied to the recorder 40. Thus, operation of the control knob 44 also operates the switch 183, through the elements 179, 177, 172 and 161, to turn on the supply of electrical power to the recorder.

As previously mentioned, selective engagement of either bank of pressure rollers 109, 110 with the tape 66 causes the respective capstan 56, 57 to drive the tape in one direction or the other (see FIGURES 17 and 19). Cooperating with this latter arrangement, means are provided for selectively rotating the spool drive posts 107, 108 on the same side of the cartridge 54 as the capstan which is driving the tape. As best observed in FIGURE 18, each spool drive post is provided with a plurality of vertical recesses, each recess receiving an outwardly bowed resilient member 185 covered with felt or the like. Hence, these members provide limited frictional contact between each spool drive post 107, 108 and the corresponding tape spool 64, 65 when the cartridge is inserted into the recorder.

In operation, the spool drive posts 107, 108 are always driven more rapidly than their corresponding capstans 56, 57. Hence, the corresponding spool 64 or 65, on the same side of the cartridge 54 as the capstan controlling movement of the tape 66, effectively takes up all of the tape driven by that capstan. However, the higher speed of the take-up spool than the capstan cannot alter the tape speed established by the capstan because of the limited frictional contact between the spool drive post and the spool. If the spool attempts to wind the tape 66 faster than the tape is moved by the driving capstan, the drag of the slower moving capstan causes slippage between the spool drive post and the spool, rather than causing a change in tape speed.

Referring to FIGURES 2, 13, 14, 18, 19 and 24, the spool drive posts are rotated by integral turntables 187, 188 at the base of each post 107, 108, respectively, and each turntable is selectively driven by one of a pair of drive rollers 190, 191, respectively. When the pressure rollers 109, are both disengaged from the tape 66 in the neutral position of the tape direction control 46, both drive rollers 190, 191 are also disengaged from their respective turntables 187, 188 (see FIGURE 14).

On the other hand, when the direction control 46 is in the forward position to bring one of the banks of pressure rollers 109, 110 into contact with the tape 66, the corresponding drive roller 190 or 191 is brought into engagement with the appropriate turntable 187, 188 (see FIGURES 19 and 24).

When the control 46 is placed in the rewind position, neither of the banks of pressure rollers 109, 110

engages the tape 66. However, in contrast to the neutral position, one of the drive rollers 190, 191 does contact its corresponding turntable 187, 188. The result is a rapid and extremely effective rewinding of the tape from one spool to the other, with virtually no tendency for the tape to break or tear free from the spool being unwound when the end of the tape is reached.

The aforedescribed rapid rewinding of the tape 66 is accomplished because neither of the capstans 56, 57 imposes any drag on the tape to cause the spool drive posts 107, 108 to slip with respect to their spools. In the absence of such slippage between the spool drive posts and the spools, the tape 66 is wound at essentially the full speed at which the appropriate drive post turntable 187 or 188 is driven. However, when the end of the tape 66 is reached, the connection between the tape end and one of the spools 64, 65 applies suflicient drag to again cause slippage between the spool post being driven and its associated spool. In other words, the resistance of the wide tape 66 against tearing free from a spool exceeds the frictional forces between the spool drive posts and the spools, so that no tape breakage can occur at the end of a rapid rewind cycle.

Positioning of the banks of pressure rollers 109, 110 and turntable drive rollers 190, 191 for the neutral, forward and rewind states, is accomplished by a rotatable and longitudinally shiftable camshaft 195 in cooperation with a pair of cam followers 197, 198 for controlling the position of the pressure rollers, and a pair of cam followers 199, 200 for controlling the positrons of the turntable drive rollers (see FIGURES 12 15 and 17).

The drive roller 190 is mounted at the upper end of the driven shaft for direct rotation with that shaft (see FIGURES 2, 18 and 24). The drive roller 191, on the other hand, is rotatably mounted at the upper end of a rotationally fixed shaft 202 (see FIGURES 2, l3 and 24). Although the shaft 202 is not a driven shaft, it will be noted in FIGURES 14, 19 and 24 that the drive rollers and 191 are always in engagement with each other, so that the roller 190 always drives the roller 191 when the roller 190 is itself driven by the shaft 140.

A pair of leaf spring elements 204 and 205 (see FIG- URES 2, 13, 18 and 24) bias the shafts 140 and 202 so that their respective drive rollers 190, 191 have a normal tendency to engage corresponding turntables 187, 188. However, each of the shafts 140, 202 is engaged by a fork 207, 208, respectively, for controlling the positrons of the shafts in accordance with the positioning of the cam followers 199, 200 by the camshaft 195 (see FIGURES 12, 13, 17 and 18). The fork 207 is coupled by an arm 210 to a pivotal shaft 211, the shaft 211 being coupled by an arm 212 to the cam folllower 199. Similarly, the fork 208 is connected to an arm 214 which is affixed to a pivotal shaft 215, the shaft 215 being connected by an arm 216 to the cam follower 200 (see FIG- URES 10, 12, 13, 17 and 18). Hence, depending upon the camming effect of the camshaft 195 upon the cam followers 199, 200, the positions of the forks 207, 208 are varied to bring their respective drive rollers 190, 191 into engagement with the corresponding spool post turntables 187, 188.

Each of the cam followers 197, 198 is connected to rocker arms 220, 221, respectively. The rocker arm 220 carries an arm 223 with a projection 224 (see FIGURES 17, 18) adapted to selectively engage and control the position of an arm 226 extending from a shaft 228. Also mounted on the shaft 228 is a rocker arm 230 which carries and controls the position of the bank of pressure rollers 109. Similarly, rocker arm 221 is provided with an arm and projection 236, 237 for engaging an arm 239, the arm 239 being in turn connected to the same shaft 241 as the rocker arm 243 which carries the bank of pressure rollers 110.

As best observed in FIGURES 2 and 17, the rocker arms 2'50 and 243 for the pressure rollers are both biased by coil springs 232, 245, respectively, so that their respective pressure rollers have a normal tendency to engage the tape 66. However, depending upon whether or not the cam followers 197, 198 are on high or low face surfaces of the camshaft 195, the pressure rollers are either forced away from the tape 66 or allowed to engage the tape. Referring particularly to FIGURE 17, it will be noted that the cam follower 197 is resting on a low surface of the camshaft 195 and, therefore, its rocker arm 220 and associated arm 223 pivot to a non-restraining position relative to the arm 226, so that the pressure roller rocker arm 230 is free to pivot the bank of pressure rollers 109 into engagement with the tape 166. However, the cam follower 198 is shown to be resting on a high surface of the camshaft 195. Hence, the rocker arm 221 and arm 236 are pivoted to a position whereby the arm 239 and pressure roller arm 243 are caused to pivot the bank of pressure rollers 110 out of engagement with the tape 66.

Referring to FIGURES 12, and 17, the camshaft 195 is provided with six sets of peripheral cam surfaces along its length, three sets on each side of center. The inner two sets of cam surfaces are for the cam followers 199, 200 which control the positioning of the rollers 190, 191 for the turntables 187, 188 (see FIGURE 14). The outer set of cam surfaces on each side of the camshaft are used to position the cam followers 197, 198 which control the positions of the banks of pressure rollers 109, 110. By shifting the camshaft 195 along its longitudinal axis, the set of cam surfaces adjacent each of the cam followers is varied to place the drive system in either the neutral, forward or rewind states of FIGURES 12, 17 and 15, respectively.

It will be observed in FIGURE 12 that, with the 'drive system in neutral, all of the cam followers 197200 rest on high surfaces of the camshaft 195. Hence, neither of the pressure rollers 109, 110 engages the tape 66, nor are either of the drive rollers 190, 191 in contact with any of the spOOl drive post turntables. Under these conditions, the tape 66 remains stationary.

As shown in FIGURE 15, when the camshaft 195 is shifted to the extreme right, to place the drive system in the rewind state, both of the cam followers 197, 198 abut high surfaces of the camshaft and, therefore, neither of the pressure rollers 109, 110 are brought into engagement with the tape 66. However, each of the cam followers 199, 200 rests against a set of cam surfaces. Hence, one or the other of the drive rollers 190, 191 is brought into driving engagement with its respective turntable to rapidly wind the tape 66 onto the spool driven by the post of that turntable.

As best observed in FIGURE 17, when the camshaft 195 is longitudinally shifted to the extreme left, all four cam followers 197200 abut a diiferent set of cam surfaces. Hence, a bank of pressure rollers and a turntable drive roller will always be engaged on one side or the other of the tape cartridge depending upon the direction of movement of the tape. It will also be noted in FIGURE 17that the camshaft 195 can be rotated about its longitudinal axis to change the positions of the cam followers 197-200, and hence alter the direction of movement of the tape66. This is exactly what occurs during a line change, when the recording head is incrementally shifted to a new line simultaneously with rotation of the camshaft 195 to alter the drive system so that the direction of movement of tape is reversed from one line to the next.

As will be apparent in FIGURES 7, 12, 15, 17 and 23, a cam follower 281 abuts the camshaft 195, and is adapted to selectively apply or release the spring-biased pressure pad 82 against the tape 66. A comparison of FIGURES 12, 15 and 17 shows that the pressure pad 82 can engage the tape 66 only when the drive system is in the forward state of FIGURE 17. When the drive system is in either the neutral or rewind states of FIGURES 12 and 15, respectively, the cam follower 231 rests upon a higher surface of the camshaft 195 and thus causes the linkage arrangement coupling the cam follower to the pressure pad to pivot the pressure pad away from the tape.

In order to provide proper clearance for insertion of the cartridge 54 into the cartridge compartment, it is necessary to move the two banks of pressure rollers 109, further away from the capstans 56, 57 than can be accomplished by the normal action of the cam followers 197, 198 riding on the camshaft in its neutral position (see FIGURE 12). Therefore, additional means are provided for camming the pressure rollers further away from the tape driving capstans when the direction control 46 is in neutral and the control 44 is in the off position (see FIGURE 12). In this connection, each of the rocker arm pivot shafts 22-8, 241 are provided with an additional arm 234, 247, respectively, adapted to be selec tively cammed by elements 249, 250 which are coupled to the on-off control 44 (see FIGURES 2, 12 and 22).

The camming element 249 is carried directly at the lower end of the shaft 179 of control 44 (see FIGURE 2). As best observed in FIGURES 22 and 23, portions also being shown in FIGURES 2, 7 and 18, the camming element 250 is coupled by a pivotal arm 252 and slide bar 253 to the control 44. The control 44 is provided with an arm 255 so that, when the control 44 is in the off position, the arm 255 cams the pivotal arm 252 to bring the element 250- into engagement with the arm 247. This shifts the bank of pressure rollers 110 further away from the capstan 57 (see FIGURE 12). Hence, with the control 44 in the off position, both banks of pressure rollers 109, 110 are shifted sufiiciently to provide adequate clearance for insertion of the cartridge 54.

When the switch 44 is moved to the on position, the only change that occurs in the structural arrangement shown in FIGURE 12 is that the camming elements 249, 250 are retracted, so that the arms 226, 239 can swing into abutment with the projections 224, 237, respectively. Hence, although the pressure rollers 109, 110 move closer to the capstans 56, 57, they are still spaced away from the tape 66 because both cam followers 197, 198 still abut high surfaces of the camshaft 195.

.The on-off control 44 also controls a number of interlocks to prevent cartridge removal when the recorder is on, and also to prevent movement of the control 46 away from the neutral position when the recorder is off. In thisconnection, the pivotal shaft 252 is provided with a depending tab 257 having a horizontal slot 259 at the end of the tab nearer the control 46 (see FIGURES 7, 10 and 11). Theshaft 49 of the control 46 pivots about a shaft 261 which has a cantilevered lock tab 263. The lock tab 263 is substantially horizontal when the control 46 is in the neutral position and, in this neutral position, the unsupported end of the lock tab 263 is in horizontal alignment with the slot 259 in the tab 257. When the control 44 is in the off position, the pivotal arm 252 moves 1 1 the tab. 257 so that the lock tab 263 is within the slot 259. With the tabs 257 and 263 interlocked in this fashion, the control 46 cannot pivot about the shaft 261 and, hence, the control 46 is locked in the neutral position.

When the control 44 is moved to the on position, the pivotal arm 252 is actuated to move the tab 257 away from the look tab 263. Hence, the tab 263 moves out of the slot 259, and the control 46 is free to pivot about the shaft 261 and place the tape drive system in the forward or rewind states.

Referring to FIGURE 7, it will also be apparent that the control 44 cannot be moved from the on position to the off position when the control 46 is in any position other than neutral. Movement of the control 46 from the neutra position to either the forward or rewind positions causes the lock tab 263 to pivot out of horizontal alignment with the slot 259 and, therefore, blocks movement of the tab 257 extending from the pivot arm 252. Hence, the control 44 cannot be returned to the off position unless the control 46 is in neutral. For this reason, a detent mechanism is used to provide positive feel when the control 46 is engaged in the neutral position. Referring to FIGURES 7 and 9, it will be observed that the detent mechanism comprises a bar 265 coupled to the shaft 49 of the control 46 and riding against a notched tab 267 carried at the free end of a cantilevered leaf spring element 269.

Referring more particularly to FIGURES 7, 22 and 23, it will be observed that the on-otf control 44 also operates means for selectively locking the cover plate a 48, once the cover has been closed and latched and the recorder has been turned on. In this regard, a slotted plate 271 is secured to the shaft 179 of the control 44 for rotation therewith. The plate 271 engages a vertical leg 273 of a slide bar 275. The opposite end of the slide bar 275 is provided with a second vertically extending leg 277. When the cartridge 54 has been inserted into the recorder 40, and the cover plate 48 has been closed, the handle 52 is used to operate the sliding latch 50. When this has been done, and the control 44 is turned on, the leg 277 moves behind a downwardly extending leg 279 of the latch 50. This, in turn, prevents the latch 50 from sliding to the left in FIGURE 23, and thus prevents the cover 48 from being opened until the control 44 is returned to the off position to shift the leg 277 out of the path of the sliding latch 50.

Referring now to FIGURE 21, the head assembly 80 includes a pair of erase heads 286, 287 with a recording and playback head 285 spaced centrally between the pair of erase heads. When the head assembly 80 is used for recording on the tape 66 rather than for playback purposes, an erase head must always lead the recording head in the recording path. Since the tape 66 moves first in one direction to record one line, and then in the opposite direction to record the next line, the erase signal must be switched from one erase head to the other at each line change. This is accomplished by means of a single pole, double throw microswitch 291 which selectively switches the erase signal input to one or the other of the erase heads 286, 287 depending upon the position of the cam follower 198 (see FIGURES 17 and 21). Since the position of the cam follower 198 controls the direction of movement of the tape 66, selective operation of the switch 291 in accordance with the position of the cam follower 198 likewise vary in accordance with the direction of tape movement.

As will be apparent in FIGURES 2, 7 and 17, the pivotal shaft 49 of the control 46 carries a small bevel gear 290 at its'lower end. The gear 290 is in mesh with a larger bevel gear 292 carried at one end of the camshaft 195. The lower end of the bar 265 coupled to the shaft 49 contacts the opposite side of the gear 292 in contact with the gear 290. With this arrangement, pivoting of the shaft 49 by the control 46 causes the camshaft 195 to shift longitudinally as shown in FIGURES 12, and 17.

Referring to FIGURES 7, 12 and 23, when the shaft 49 is rotated by the control knob 46, the gear 290 drives gear 292 to rotate the camshaft 195. This rotation'of the camshaft causes position and thereby alter the drive system to move the tape in the proper direction for the particular line selected by rotation of the control 46. The center of the camshaft 195 is processed to provide a gear 297 of slightly reduced diameter than the maximum diameter of the camshaft. The gear 297 is in mesh with a large spur gear 299 which is affixed to a shaft 306 passing through its axis of rotation, the shaft 306 being also coupled to the line indicating disc 47. Hence, line selection by rotation of the control 46 automatically brings about an indication of the selected line via the disc 47.

Mounted on the same shaft 306 as the gear 299, is a small pinion gear 301 which drives a rack 302. The head assembly is affixed, between a pair of guide posts 303, 304, to the upper end of the rack 302 for movement with the rack. Hence, rotation of the control 46 to change lines automatically shifts the head assembly 80 to the selected line, automatically rotates the camshaft to cam the drive system into the proper state for driving the tape in the appropriate direction for the selected line, and automatically indicates the selected line by the disc 47.

To prevent damage to the head assembly 80 by moving the rack 302 too far in either direction, an automatic stop arrangement is used to limit rotation of the camshaft 195 by the control 46 to a specified number of complete revolutions which will not drive the rack beyond safe limits for the head assembly. This stop means is best observed in FIGURES 7, 12, 31 and 32 and comprises a collar 310 secured to the camshaft 195, together with a pair of discs 312, 314 which are both mounted on the shaft 195 adjacent the collar 310, but both discs 312, 314 are rotatable with respect to the camshaft and each other. The diameters of the discs and collar in the stop assembly also vary, the collar 310 having the smallest diameter and the outer disc 314 having the largest diameter.

As best observed in FIGURES 7, 31 and 32, a pair of spaced apart, fixed flanges 316, 318 are provided adjacent the stop assembly. The collar 310 and each of the discs 312, 314 are each provided with peripheral tabs 320-322, respectively. The peripheral tab 320 overlaps the tab 321 but not the tab 322. The peripheral tab 321., in turn, radially overlaps the tab 322. The flanges 316, 318 are positioned so that the tab 322 cannot clear either flange during rotation of the disc 314, but either of the tabs 320, 321 will clear the flanges during rotation of the collar 310 and disc 312, respectively.

The arrangement illustrated in FIGURES 31 and 132 limits rotation of the shaft 195 to three revolutions from the upper stop position of FIGURE 31 to the lower stop position of FIGURE 32 and vice versa. In moving from the upper stop position to the lower stop position, the shaft 195 is rotated counterclockwise in FIGURE 31. During the first revolution, the collar 310 rotates with the shaft 195 and the tab 320 clears the lower flange 316 to contact the underside of the tab 321 upon the disc 312. During the second revolution, both the collar 310 and disc 312 rotate with the shaft 195 and clear the flange 316 to bring the tab 321 into abutment with the underside of the tab 322.During the third revolution, the collar and both discs rotate with the shaft 195, and the tab 322 is stopped by the lower flange 316 to prevent further rotation of the camshaft 195. The sequence is exactly the same is moving from the lower flange 316 to the upper flange 318. The number of revolutions to which the shaft 195 is limited may be varied in accordance with the number of discs used in the stop assembly, i.e., one additional permissible revolution for each additional disc.

the cam followers 197-200 to shift their The structure of the automatic line change mechanism is best observed in FIGURES 7, 18 and 2330. At each end of the tape 66, the tape is provided with a triggering hole '93, preferably triangular in shape and in alignment with one of the openings 84, 85 in the cartridge 54. The triggers 87, 88, preferably conical in shape, extend through the openings 84, 85 in the cartridge and rest against the tape 66 as the tape moves. When an end of the tape is reached, the triggering hole 93 at that end of the tape comes into registry with the cartridge opening 84 or 85 at that end, and the respective trigger 87, 38 will slip into the hole 93 and be carried along with the tape to trip the automatic line change mechanism and reverse the direction of movement of the tape.

Each of the triggers 87, 88 is a unidirectional triggering device, in that the opening 93 in tl e tape will catch and drive the trigger in one direction but will release the trigger in the other direction. In this connection, the wide base of the conical trigger element 87, 88 should face in the direction opposite to that in which the tape moves to bring about triggering, and the apex of the conical trigger should face in the same direction as the desired triggering movement of the tape.

The trigger mechanisms for both ends of the tape are similarly mounted, but face in opposite directions. The trigger 87 is mounted for sliding movement along a horizontal shaft 325 which extends from a pivotal plate 326. The plate 326 is secured to a pivot shaft 327, and is biased towards the cartridge housing 60 by a leaf spring element 328 in abutment with an arm 330 extending from the lower end of the plate 326. By biasing the plate 326 towards the cartridge housing 60 in this manner, the trigger 87 is thus biased against the tape 66.

A trip rod 332 has one end slidably mounted upon the shaft 325 adjacent the apex of the trigger 87. The opposite end of the trip rod 332 is connected to a trigger push rod 334, the trip rod 332 being pivoted above the push rod at 336. Hence, when the trigger 87 engages the hole 93 and is carried by the tape 66, the upper end of the trip rod 332 is carried with the trigger along the shaft 325. This causes the trip rod to pivot at 336 and move the push rod 334 to the left in FIGURES 7, 25 and 27. The mounting and biasing arrangement for the trigger 88 is essentially a mirror image arrangement of that for the trigger 87, except that the trip rod 34!} is pivoted below the push rod 334 so that movement of the trigger 88 also causes the push rod 334 to move to the left.

A slide bar 345 is supported just above the cam fol lower rocker arms 226, 221 (see FIGURE 7). This slide bar 345 has a depending tab 347 (see FIGURES 7 and 23) which abuts the gear 297 of the cam shaft 195. Since the gear 297 has a maximum outer diameter which is less than the maximum diameter of the camshaft 195, a pair of shoulders are provided by the camshaft on each side of the gear 297 to carry the tab 347 with the camshaft whenever the shaft is shifted longitudinally. Hence, Whenever the camshaft 195 is shifted by the control 46, for placing the drive system in the neutral, forward or rewind states, the tab 347 and slide bar 345 are also shifted with the camshaft.

As best observed in FIGURES 7, 18, 23' and 24, the slide bar 345 has a pair of cantilevered members 350, 351, which overlie each of the pivot arms 330, 338 of the triggers 87, 88, respectively. The members 350, 351 are each shaped to'define two zones of differing spacing between the members and the slide'bar 345, the smaller spacing zone being further to the left, and the zone of greater spacing being further to the right adjacent the free end of each member.

,When the control 46 is pivoted to the right in FIGURE 7, to place the drive system in the forward state, the camshaft 195 and slide bar 345 are moved to their extreme left positions. This permits the arms 330 and 338 of the triggers 37, 88, respectively, to pivot upwardly under the influence of their respective leaf spring 14 elements 328, 339, so that the triggers are biased against the tape 66. However, when the control 46 is pivoted to the left to place the drive system in either the neutral or rewind states, the camhsaft 195 and slide bar 345 are moved to their extreme right positions in FIGURE 7. When this occurs, the pivot arms 330' and 338 of the line change triggers are placed within the zones of narrow spacing between the members 355, 351 and the slide bar 345. Under these conditions, the biasing forces of the leaf spring elements 328, 339 are overridden by the members 354 351, and the triggers 87, 88 are pivoted out of engagement with the tape 66 (see FIGURE 18). This pivoting of the line change triggers 87, 88 out of engagement with the tape 66 is of particular significance when the drive system is in the rewind state, since it is desired that the tape is rewound without the hole 93 at the end of the tape causing any triggering of the automatic line change mechanism.

The push rod 334 releases a spring-wound ratchet mechanism each time it is moved to the left, and this ratchet system rotates the camshaft 195 each time it is released, to cause a single line change. As observed in FIGURE 16, the ratchet 354 issuccessively spring biased against one or the other of a pair of pawls 356, 357. Each time the push rod 334 is moved to the left (see FIGURE 25) One of the pawls 356, 357 is momentarily shifted out of the path of the ratchet 354, so that the ratchet moves through to abut the other pawl.

The ratchet 354 is mounted on a shaft 359 carrying a small spur gear 361. The gear 361 is in mesh with a larger spur gear 363 adapted to drive the camshaft 195. When the camshaft is rotated, the camshaft gear 297 rotates the gear 299 which, in turn, rotates the pinion 351 to drive the rack 302 and thereby shift the head assembly 80 to a new line on the tape.

The means for selectively releasing the ratchet 354 one step at a time, by actuation of the push rod 334, are best observed in FIGURES 27-30. The camshaft 195 is adapted. to have one end slidably received within an internal keyway 365 of a drum 366. The end of the camshaft inserted into the keyway is provided with a transverse bore 368 in which are placed a pair of oppositely disposed spring-loaded balls 370.

A torsion spring 372 (see FIGURE 29) biases the gear 363 and drum 366. The drum 366 would ordinarily rotate under the influence of the spring 372 except for the restraining action of the ratchet 354 and pawls 356-, 357. However, the ratchet and pawl arrangement have no restraining etfectnpon manual line changing by rotation of the camshaft 195. The reason for this is that the springloaded balls allow the camshaft 195 to slip with respect to the drum 366 when any attempt is made to rotate the camshaft while the drum is being held stationary by the ratchet and pawl mechanism. However, when one of the pawls 356, 357 is momentarily shifted to release the ratchet 354, the spring 372 momentarily encounters little resistance and, therefore, drives both the drum 366 and camshaft 195 through an automatic single line change.

It will be noted in FIGURES 16 and 28 that the shape of the outer end of the ratchet 354 is such that rotation of the ratchet is restrained by the pawls 356, 357 only in a single direction. If the ratchet 354 is rotated in the opposite direction, the canted or curved end face 375 of the ratchet automatically cams the pawls 356, 357 out of the path of the ratchet. Hence, the automatic line change mechanism only is effective to make line changes in ascending order, e.g., lines 1 to 2, 2 to 3, 3 to 4, etc.

Return to the first line on the tape must be accomplished manually by rotation of the line selector control 46. When the camshaft 195 is rotated manually in this manner, to return to earlier lines on the tape, both the drum 366 and ratchet 354 rotate without restraint with the camshaft. However, manual rotation of the camshaft 195 to move the direction of ascending order of lines upon the tape, always encounters resistance due to the ratchet and pawl arrangement, and thus causes the camshaft to slip with respect to the drum 366.

Whenever the'camshaft 195 is manually rotated to return to earlier recording lines on the tape, rotation of the drum 366 with the camshaft also rewinds the torsion spring 372, so that the spring can bias the system through automatic line changes over the entire usable width of the tape. However, since the camshaft 195 slips with respect to the drum 366 when the camshaft is rotated in the opposite direction, the spring 372 is never unwound by manual rotation of the camshaft via the control 46.

To prevent overwinding of the spring 372, a stop arrangement, in the form of three drum segments 374, 375, 376 having overlapping peripheral tabs 378380, respectively, cooperate with a fixed member 382 in the same manner as the stop system for the camshaft 195 illustrated in FIGURES 31 and 32. Hence, the spring 372 is protected by limiting the number of revolutions of the drum 366 which wind the spring.

The push rod 334 has its leading end in abutment with a slightly flexible plate 385 having a mutually perpendicular and also slightly flexible strip 386 positioned behind the plate. A leaf spring 388 biases the plate 385 and push rod 334 to the right, so that the plate 385 does not contact the strip 386 until the tape triggers drive the push rod 334 to the left to override the spring 388. When the latter occurs, the strip 386 contacts and rotates one or the other of a pair of pivot arms 390, 391 secured to the pawl pivot shafts 393, 394, respectively. Rotation of either of the arms 390, 391 causes the corresponding pawl 357, 356 to shift out of engagement with the ratchet 354 so that the latter may rotate through 180.

When the ratchet 354 rotates, the spur gear 361 rotates with it and. drives a coaxial eccentric 396 through 180". Rotation of the eccentric 396 causes a forked member 398 to pivot slightly about a shaft 400. Carried on the face of the member 398 is another forked element 403 engaging the trigger strip 386 and moving the latter each time member 398 is pivoted.

The operation of the system is as follows: Movement of the push rod 334 to the left causes the trigger strip 386 to pivot one of the arms, e.g., 390, to shift the pawl 357 and release a ratchet 354- through 180. When the ratchet rotates, the gear 361 rotates with it to drive the large gear 363 which, in turn, drives the drum 366 and camshaft 195 through a single line change in ascending numerical order. Rotation of the ratchet 354 also rotates the eccentric 396 which, through members 398 and 492, shifts the slightly flexible trigger strip 386 to a position adjacent the pivot arm 391. With the trigger strip 386 thus positioned, upon the next stroke of the push rod 334, the next pawl 356 will be shifted to again release the ratchet 354 through another 180 and return it to its original position adjacent the pawl 357. This sequence of events is repeated each time the push rod 334 is driven to the left in FIGURE 27 by one of the tape triggers 87, 88, each pawl 356 or 357 being shifted on alternate strokes.

It will be apparent from the foregoing that, while a particular form of my invention has been illustrated and described, various modifications can be made without departing from the spirit and scope of my invention. Accordingly, I do not intend that my invention be limited, except as by the appended claims.

I claim:

1. In a tape recorder, the combination comprising:

a cartridge containing a length of magnetic tape;

a pair of pivotally mounted tape driving capstans;

means for biasing the outer ends of said capstans towards each other;

means within said cartridge for camming the outer ends of said capstans away from each other and bringing said capstans into contact with said tape when said cartridge is inserted onto said capstans;

means for rotating each of said capstans continuously in opposite directions after insertion of said cartridge;

and pressure roller means for selectively pressing said tape against one or the other of said capst-ans to drive said length of tape in either of two directions.

2. Magnetic tape recording apparatus, comprising:

a cartridge;

a length of magnetic tape supported within said cartridge;

a pair of pivotally mounted tape driving capstans having their outer ends normally biased towards each other;

a bearing cap mounted at the outer end of each of said capstans, each bearing cap being rotatable with respect to its capstan;

means within said cartridge for camming said capstan's away from each other and into positions adjacent said tape when said cartridge is moved over said capstans;

means for continuously rotating said capstans in opposite directions;

and .a pair of pressure roller means for selectively pressing said tape against one of the rotating capstans to drive said length of tape in a first direction, and for selectively pressing said tape against the other of said rotating capstans to drive said length of tape in the opposite direction.

3. In a tape recording system having a pair of spools supporting a length of tape, the combination comprising: a pair of parallel, tape driving capstans in contact,

with said tape;

a pair of spool drive posts in driving engagement with said spools;

a respective drive roller rotatable to drive one of said spool drive posts in the same direction as the capstan nearer the post to be rotated;

means for continuously rotating each of said capstans in opposite directions and for continuously rotating each of said drive rollers in opposite directions;

restraining means for each of said drive rollers to maintain the drive rollers out of driving engagement with said spool drive posts;

a pair of pressure roller means, each closely adjacent to but spaced from one of said tape driving capstans;

camming means for selectively actuating one of said pressure roller means to press said tape against the adjacent capstan for driving said length of tape, said camming means also selectively disabling one of said restraining means to bring one of said drive rollers into driving engagement with the spool drive post nearer the capstan driving said tape;

means for varying said camming means to alter the positions of said pressure roller means and said drive rollers so that the other capstan and spool drive post post nearer the capstan driving said tape;

and means for further varying said camming means to maintain both of said pressure roller means out of engagement with said tape and selectively bring one or the other of said drive rollers into engagement with one of said spool drive posts.

4. Apparatus as set forth in claim 3, wherein said camming means includes a multi-position camshaft and a plurality of cam followers for controlling the positions of said pressure roller means .and said drive rollers.

5. Apparatus as set forth in claim 3, including:

a surface irregularity at each end of said length of tape;

and trigger means responsive to the surface irregularity at each end of said length of tape for conditioning said camming means to reverse the direction in which said length of tape is driven.

6. Apparatus as set forth in claim 5, including means for disabling said trigger means whenever said camming means has been varied to bring one of said drive rollers 17 into driving engagement with one of said spool drive posts while both of said pressure roller means are out of engagement with said tape.

7. In combination with a length of tape having its ends secured to a pair of spools, a tape driving system, comprising:

a pair of parallel, tape driving capstans adjacent said tape;

means for rotating each of said capstans continuously in opposite directions;

a pair of spool drive posts in driving engagement with said spools;

a pair of pressure rollers, each pressure roller being adjacent one of said capstans and selectively movable to press said tape against a capstan;

a pair of drive rollers, each roller being adapted to selectively drive one of said spool drive posts;

means for continuously rotating each of said drive rollers in opposite directions;

a camshaft having a plurality of cam surfaces about its periphery and along its length;

a plurality of cam followers abutting said camshaft for controlling the positions of said pressure rollers and said drive rollers relative to said tape and said spool drive posts, respectively;

first means for selectively rotating and longitudinally shifting said camshaft along its longitudinal axis to adjust said cam followers to a first state wherein one or the other of said pressure rollers is in engagement with said tape and one or the other of said drive rollers is in driving engagement with one of said spool drive posts, to a second state wherein neither of said pressure rollers engages said tape and neither of said drive rollers engages any of said spool drive posts, and to a third state wherein neither of said pressure rollers engages said tape and one of said drive rollers is in driving engagement with one of said spool drive posts;

and normally inactive second means for rotating said camshaft to adjust said cam followers only with respect to said first state.

8. Apparatus as set forth in claim 7, including additional camming means for selectively increasing the spacing between said tape and both of said pressure rollers when said cam followers are in the second state and neither of said capstans or said drive rollers is rotating.

9. Apparatus as set forth in claim 7, including trigger means responsive to a surface irregularity at either end of said length of tape to activate said second, means and thereby reverse the direction of movement of said tape.

10. In combination with'a length of tape having a surface irregularity at each end of said length of tape:

tape driving means;

control means for said tape driving means for reversing the direction of movement of the tape;

a pair of slidable triggers to engage the tape, each trigger being movable by and with said tape when the trigger encounters a surface irregularity at the end of said tape, movement of one trigger by the surface irregularity at one end of said tape being in the opposite direction to movement of the other trigger by the surface irregularity at the other end of said tape;

an elongated push rod;

and a pair of pivotal trip rods, each trip rod having one end coupled for movement with one of said triggers and each at its other end engaging and longitudinally moving said push rod when the trip rod is pivoted by its respective trigger.

11. A combination as set forth in claim 10, wherein pivotal movement of either of said trip rods always drives said push rod in the same direction.

12. In combination with a length of tape having a surface irregularity at each end of said length of tape:

tape driving means;

control meansfor said tape driving means for reversing the direction of movement of the tape;

a pair of slidable triggers to rest on the tape, each trigger being movable by and with said tape when the trigger encounters a surface irregularity at the end of said tape, movement of one trigger by the surface irregularity at one end of said tape being in the opposite direction to movement of the other trigger by the surface irregularity at the other end of said tape;

an elongated push rod;

a pair of pivotal trip rods, each rod having one end coupled for movement with one of said triggers and each at its other end engaging and longitudinally moving said push rod in a single, common direction when the trip rod is pivoted by its respective trigger;

means for biasing said triggers into contact with said tape when said tape driving means is in the forward drive state;

and disabling means for lifting said triggers out of contact with said tape when said tape driving means is not in the forward drive state.

13. In a tape recorder, the combination comprising:

a cartridge containing a length of magnetic tape;

a pair of capstans supported at one end for rotation, said capstans being normally non-parallel but being relatively movable so as to be parallel,

said cartridge having openings to receive the other ends of said non-parallel capstans;

capstan moving means operable upon forcing said cartridge onto said capstans to bring said capstans into parallel relation;

means for rotating said capstans in opposite directions;

and pressure roller means adjacent each capstan for selectively pressing said tape against one or the other of said capstans.

14. For use in tape recorder apparatus having spaced, normally non-parallel capstans capable of relative movement so as to be parallel, and a magnetic transducer intermediate the capstans, the combination of:

a pair of reels supporting a length of magnetictape;

a housing having front, back and top walls, said housing having compartments in which said reels are located between said front and back walls on parallel axes;

means in said housing supporting the portion of the tape intermediate said reels for movement adjacent said top wall, said'top wall having an opening intermediate its ends through which part of the intermediate tape portion is exposed to the exterior of said housing 7 v said front wall having openings 'to receive the ends of the non-parallel capstans, said front wall openings being positioned so that the ends of the capstans can enter the housing between the respective reels and the parts of the intermediate tape portion adjacent to such reels;

and cam means in said housing and operable, when the housing is forced onto the ends of the capstans, to effect relative movement of the capstans and bring them into parallel relation, the exposed portion of the tape being engageable by the transducer when said housing is on the ends of the capstans.

15. The combination of claim 14, wherein said support means for the intermediate tape portion constitutes a pair of elements in said housing adjacent said front wall openings, said elements having top surfaces adjacent said top wall and over which said intermediate tape portion passes,

and wherein said cam means includes edge surface portions of said elements adapted to be engaged by the ends of the capstans entering said front wall openings, said edge surface portions extending inwardly of said housing at an angle so as to cause the ends 19 r of both capstans to move to the positions in which, when the housing has been forced onto the capstans, the capstans are parallel.

16. The combination of claim 15, wherein said top wall has openings adjacent its ends to expose the portions of the tape engaged by the capstans through which to selectively press said tape against one or the other of the capstans.

17. For use in a tape recorder apparatus having spaced, normally non-parallel capstans capable of relative movement so as to be parallel, and a magnetic transducer intermediate the capstans, a cartridge comprising:

a pair of reels;

a length of tape having its ends attached to said reels,

said tape having openings therein adjacent its ends;

a housing having front, back and top walls;

a shelf member in said housing having a pair of spaced surface portions adjacent to said top wall, said surface portions having openings therein,

said top wall having openings therein aligned with said openings in said surface portions,

said housing having compartments below said shelf member, said reels being located in said compartments on parallel axes between said front and back walls,

the portion of said tape intermediate said reels extending over and along said surface portions of said shelf member,

said housing having openings intermediate said firstmentioned openings therein and through which said intermediate tape portion passes and is exposed to the exterior of said housing,

said front wall having respective openings adjacent the ends of said shelf member to receive the ends of the non-parallel capstans, said front wall openings being positioned so that the ends of the capstans can enter the housing between the respective reels and the parts of the intermediate tape portion adjacent to such reels; and

cam means in said housing and operable, when the housing is forced onto the ends of the captans, to effect relative movement of the capstans and bring them into parallel relation, the exposed portion of the tape being engageable by the transducer when said housing is on the ends of the capstans.

18. The assembly of claim 17, wherein said top wall has openings adjacent the ends thereof through which are exposed the portions of the tape adjacent the ends of said shelf member.

19. The assembly of claim 17, wherein the ends of said shelf member having concave edges, the portions of said concave edges adjacent said back wall being parallel, the remaining portions of said concave edges ex- 28 tendingforwardly from saidparallel portions to said front wall openings,

said front wall openings extending longitudinally in said front wall, the adjacent ends of said front wall openings and the concave edges of said shelf member being similarly curved, and said back wall having openings adjacent its ends, said back Wall openings and the remote ends of said oblong openings being similarly curved.

20. The assembly of claim 17, wherein said front wall openings extend longitudinally in said front wall, the remote ends of said front wall openings being larger than their adjacent ends, and said back wall having openings therein aligned with the enlarged portions of said front wall openings.

21. In a tape recorder, the combination comprising:

a cartridge containing a length of magnetic tape;

a pair of pivotally mounted tape driving capstans;

means for biasing the outer ends of said capstans to wards each other; and

means within said cartridge for camming the outer ends of said capstans away from each other and bringing said capstans into contact with said tape when said cartridge is inserted-onto said capstans.

22. For use in a tape recorder having spaced, normally non-parallel capstans capable of relative movement so as to be parallel, a cartridge comprising:

a cartridge housing;

means for supporting a length of magnetic tape within 30 said housing; and

capstan moving means operable upon forcing said cartridge onto said capstans to bring said capstans into parallel relation adjacent said tape.

References Cited UNITED STATES PATENTS TERRELL W. FEARS, Primary Examiner.

BERNARD KONICK, Examiner. L. G. KURLAND, V. I. QANNEY, Assistant Examiners. 

1. IN A TAPE RECORDER, THE COMBINATION COMPRISING: A CARTRIDGE CONTAINING A LENGTH OF MAGNETIC TAPE; A PAIR OF PIVOTALLY MOUNTED TAPE DRIVING CAPSTANS; MEANS FOR BIASING THE OUTER ENDS OF SAID CAPSTANS TOWARDS EACH OTHER; MEANS WITHIN SAID CARTRIDGE FOR CAMMING THE OUTER ENDS OF SAID CAPSTANS AWAY FROM EACH OTHER AND BRINGING SAID CAPSTANS INTO CONTACT WITH SAID TAPE WHEN SAID CARTRIDGE IS INSERTED ONTO SAID CAPSTANS: MEANS FOR ROTATING EACH OF SAID CAPSTANS CONTINUOUSLY IN OPPOSITE DIRECTIONS AFTER INSERTION OF SAID CARTRIDGE; AND PRESSURE ROLLER MEANS FOR SELECTIVELY PRESSING SAID TAPE AGAINST ONE OR THE OTHER OF SAID CAPSTANS TO DRIVE SAID LENGTH OF TAPE IN EITHER OF TWO DIRECTIONS. 